A growing trend in search engine technology is the display of specialized content such as news, products and the like that are associated in some way (e.g., interleaved) with traditional web search results. In general, this content should be displayed only when highly relevant to the search query, as it competes for space with additional search results and advertisements.
One measure of the relevance of specialized content to a search query is the click-through rate, corresponding to how often a link to the specialized content is clicked when displayed. For some types of queries for which specialized content has been displayed enough times, the click-through rate can be tracked. However, this does not work well when dealing with a query for which the click-through rate is not known, such as news queries which tend to be about current events and are ever changing over time. Further, it is generally not desirable to put anything that may be irrelevant on a results page just for the purpose of collecting click-through data, as irrelevant results tend to annoy users.